The applicant organization has discovered and experimentally observed that an Electroacoustical Compensation (ELAC) circuit counteracts the occlusion effect experienced by hearing aid wearers of unvented hearing aids. Unvented hearing aids with the ELAC circuit show promise for a significant improvement over present vented designs in the following areas: 1) Higher available gain before positive feedback oscillation, 2) Reduced amplifier and receiver distortion, 3) Reduced direct transmission of ambient noise, 4) Better low-frequency response (if needed), 5) Better suited for in-the-canal devices. In view of the seven-year involvement with occluded in-the-ear communication device design based on ELAC circuit, the applicant will be able to design, fabricate, and perform a limited evaluation of ELAC hearing aids within the limited time and resources of the proposed Phase I study. All facilities are in place.